720^ 



The length of the head is thus contained 4,37 times in the total 

 length (3,91 times in the length to the tip of the central caudal rays); 

 the diameter of the eye is contained 2,70 times in the length of the 

 head; and the height of the body 6 times in the total length. 



The fins. The pectorals are comparatively long, and reach with 

 their tips to the root of the ventrals, covering the supra-ventral spot 

 (antero-lateral, Go od e & Bean). 



The tip of the ventral reaches to the vent, its length being greater 

 than half the length of the head. 



The luminous glands are immense, and shine with a bright, silky 

 lustre. The ventral one is the longest, and covers a surface corre- 

 sponding in length to 9 Y2 o^ the scales of the lateral line. It begins 

 immediately behind the anal, and ends a little in front of the first rudi- 

 mentary rays of the caudal. 



The dorsal gland is somewhat shorter, and covers only about 

 8 scales of the lateral line. It begins in the vertical from the first third 

 of the ventral gland, and extends very slightly farther back, exactly to 

 the beginning of the rudimentary rays of the caudal. 



The length of the ventral gland is 13 mm, that of the dorsal one 

 10 mm, both of them being thus considerably longer than the diameter 

 of the eye. 



The photophores, which are very small and rather difficult to 

 trace in their entirety, are als follows': 



M. operculares (Op.) 2, on the praeoperculum ; the one situated 

 about half-way between the orbit and the upper P. V., the other in the 

 vicinity of the isthmus. 



M. ante-orbitales (A. Orb.) 2, exceedingly small, fairly close tog- 

 ether, and lying exactly on the anterior margin of the orbit. 



M. branchiostegae (Brr.) 3, normal. 



M. pectorales (P.) 5 ; the foremost lies near the isthmus, and is se- 

 parated from the second by a space ; the second, third and fourth form 

 a slight curve, but the fifth lies higher than the rest, in front of the 

 base of the uppermost ventral rays. 



The fourth (last but one) spot is here situated no higher than the third. 



M. sup-pectorales (P.V.) 2, the upper one immediately in front of 

 the base of the pectoral, the lower one vertically over the space between 

 the first and second pectoral spots. 



M. supra-pectoralis (P.L.) 1, a little below the lateral line, and 

 almost vertically over the base of the uppermost rays of the pectoral. 



■^ I employ the nomenclature adopted by Dr. Brauer in his excellent mono- 

 graph on the genus Myctopl/am, in Zool. Anz. Yol. 28. No. 10. p. 377. (Dec. 1904). 



51 



